Baffin Island Wolf (Canis lupus manningi)

Northern Canadian Shield taiga, Baffin coastal tundra, Davis Highlands tundra, High Arctic tundra, Low Arctic tundra, Middle Arctic tundra

A wolf-sighting questionnaire was sent to 201 arctic field researchers from many disciplines to solicit information on observations of wolves (Canis lupus spp.) made by field parties on Canadian Arctic Islands. Useable responses were obtained for 24 of the 25 years between 1967 and 1991. Respondents reported 373 observations, involving 1203 wolf-sightings. of these, 688 wolves in 234 observations were judged to be different individuals; the remaining 515 wolf-sightings in 139 observations were believed to be repeated observations of 167 of those 688 wolves. The reported wolf-sightings were obtained from 1953 field-weeks spent on 18 of 36 Arctic Islands reported on: no wolves were seen on the other 18 islands during an additional 186 field-weeks. Airborne observers made 24% of all wolf-sightings, 266 wolves in 48 packs and 28 single wolves. Respondents reported seeing 572 different wolves in 118 separate packs and 116 single wolves. Pack sizes averaged 4.8 ± 0.28 SE and ranged from 2 to 15 wolves. Sixty-three wolf pups were seen in 16 packs, with a mean of 3.9 ± 2.24 SD and a range of 1 -10 pups per pack. Most (81%) of the different wolves were seen on the Queen Elizabeth Islands. Respondents annually averaged 10.9 observations of wolves . 100 field-weeks⁻¹ and saw on average 32.2 wolves . 100 field-weeks⁻¹ yr⁻¹ between 1967 and 1991. Average rates of wolf observations . 100 field-weeks⁻¹ (28.5, 13.6 vs. 5.7; p < 0.005) and mean numbers of different wolves seen-100 field-weeks⁻¹ (92.3, 37.5 vs. 15.4; p < 0.005) were markedly greater during 1967-75 and 1989-91 than in 1976-88. Relative differences in the reported rates of wolf observations on the Queen Elizabeth Islands in 1967-75,1976-88, and 1989-91 follow the relative abundance of the wolf major prey, Peary caribou (Rangifer tarandus pearyi) and muskoxen (Ovibos moschatus), on those islands during those periods.

Wolves in the Canadian Arctic Archipelago face several challenges to persistence: a harsh habitat, an unstable prey base, and potentially significant anthropogenic influences. These external factors, if combined with genetic constraints common to island populations, could be particularly difficult to withstand. To determine the genetic status of Arctic Island wolves, we used 14 microsatellite loci to estimate population variation and the extent of inter-island and island-mainland gene flow. All island populations were significantly less variable than mainland wolves; although inbreeding is currently insignificant, the two least variable populations, Banks and the High Arctic (Ellesmere and Devon Islands), showed genetic signatures of recent population declines. Recovery after a bottleneck appears to result, in large part, via recolonization from other islands. These extinction-recolonization dynamics, and the degree of similarity among island wolves revealed by Bayesian clustering, suggest that Arctic Island wolves function as a metapopulation. Persistence of the metapopulation may be supported by periodic migration from mainland populations, occurring primarily through two corridors: Baffin Island in the Eastern Arctic, and Victoria Island in the Western Arctic. This gene flow could be compromised or eliminated by loss—due to climatic warming or increased human activity—of sea ice in the Northwest Passage.

Wolves (Canis lupus) and arctic foxes (Alopex lagopus) are the only canid species found throughout the mainland tundra and arctic islands of North America. Contrasting evolutionary histories, and the contemporary ecology of each species, have combined to produce their divergent population genetic characteristics. Arctic foxes are more variable than wolves, and both island and mainland fox populations possess similarly high microsatellite variation. These differences result from larger effective population sizes in arctic foxes, and the fact that, unlike wolves, foxes were not isolated in discrete refugia during the Pleistocene. Despite the large physical distances and distinct ecotypes represented, a single, panmictic population of arctic foxes was found which spans the Svalbard Archipelago and the North American range of the species. This pattern likely reflects both the absence of historical population bottlenecks and current, high levels of gene flow following frequent long-distance foraging movements. In contrast, genetic structure in wolves correlates strongly to transitions in habitat type, and is probably determined by natal habitat-biased dispersal. Nonrandom dispersal may be cued by relative levels of vegetation cover between tundra and forest habitats, but especially by wolf prey specialization on ungulate species of familiar type and behaviour (sedentary or migratory). Results presented here suggest that, through its influence on sea ice, vegetation, prey dynamics and distribution, continued arctic climate change may have effects as dramatic as those of the Pleistocene on the genetic structure of arctic canid species

A study of the ecology of the Baffin Island tundra wolf (Canis lupus manningi) was conducted in an 1800 square mile area on central Baffin Island in the spring and summer 1966-69, in order to further the understanding of the relationship between this predator and its single large prey species, the caribou.

The migratory tundra caribou/reindeer in the Holarctic now number three million and are increasing, approaching estimated pristine quantities in North America. In contrast, the sedentary forest races south of the tree-line number about 325 000 animals, and are declining in some areas in both Eurasia and North America. The chief natural mortality factor determining the survival of neonates and adults is predation; the wolf is the major predator. Recruitment and natural adult mortality are approximately equal when wolf numbers are about 6.5 per 1000 km². Wolf numbers have been reduced north of the tree-line in the Nearctic since the 1970s due to hunting facilitated by snowmobile transportation. But south of the tree-line wolf numbers may be locally high (>8 per 1000 km²) where moose have expanded their range in this century. Caribou can adapt to economic development in the Arctic if their space for mobility to cope with their predators is kept inviolate. It should be possible, through management of wolf numbers, to increase further the abundance of caribou and wolves and provide surpluses of both species for northern peoples, yet maintain a viable large mammal ecosystem in the Arctic.